Abstract: Disclosed is method of protecting skin from ultraviolet radiation which comprises the step of administering a skin protective composition. The skin protective composition disclosed in the present invention includes a compound, which not only can protect normal human skin against UV-induced damage, but also exhibits protective benefits on the skin of patients with G6PD-deficiency.

Abstract: A method of detecting and measuring levels of a sulfur-containing amino acid in a sample is provided. The method includes combining an enzyme with an aqueous solution possibly comprising a sulfur-containing amino acid. When a sulfur-containing amino acid is present in the solution, it reacts with the enzyme and produces hydrogen sulfide or ammonia. An electrochemical sensor is employed to detect the presence of hydrogen sulfide or ammonia in the solution, and thereby detect the presence of sulfur-containing amino acid. The concentration of sulfur-containing amino acid present in the sample can be quantitatively measured or calculated using this method.